Via NikonRumors, this is something everyone should know about: a do-it-yourself $30 wifi kit for the Nikon D4! It really speaks for itself. Read on for the details. Who knows, maybe something similar could be done for the 1D X. I wouldn't be surprised at all...
This is what NikonRumors had to say:
The NR reader Voudas sent me this inexpensive alternative for controlling your NikonD4 camera through WiFi:
"The idea was to connect the small VAP11G portable WiFi bridge device (available on eBay and Amazon) to the D4's Ethernet port in order to use it through WiFi. I setup the Ethernet connection of the D4 and then used the VAP11G device to connect through my WiFi. I then used my laptop and iPhone to check the WiFi connectivity with the D4. It worked like a charm!
The limitation of the device is that it didn't act as an access point - it would always need an established WiFi network, but the important thing was to prove that the price of the WT-5 price is ridiculously high ($877) and the VAP11G does the same thing for around $30. This limitation could probably be eliminated with the Asus WL-330gE wireless access point."
Hear's a link to get that bridge device on Amazon.